bos taurus vs. bos indicus

9
1 Synchronization Response: Bos taurus vs. Bos indicus Cattle Joel V. Yelich, PhD Department of Animal Sciences University of Florida, Gainesville 2012 Beef Improvement Federation Houston, Texas G. Allen Bridges, PhD University of Minnesota North Central Research and Outreach Center Grand Rapids, MN Bos taurus beef cattle Maternal and(or) terminal breeds Positive carcass traits: marbling,tenderness, yield Excellent production in temperate climates Bos indicus Based Cattle “Positive Attributes” Heat tolerant Increased parasite & disease tolerance Improved production in subtropical climates Bos indicus Based Cattle “Negative Attributes” Older age at puberty Decreased carcass quality & tenderness Potential handling stress issues Management driven Reproductive challenges with Bos indicus cattle Differences in concentrations and (or) sensitivities to GnRH, LH, estrogen, and progesterone Increased incidence of estrous cycles with three and four follicle waves Difficult to detect estrus, due to shorter estrous duration, decreased estrous intensity, and increased incidence of silent heats Postpartum period is extended More susceptible to (-) effects of handling stress

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Page 1: Bos taurus vs. Bos indicus

1

Synchronization Response: Bos taurus vs. Bos indicus Cattle

Joel V. Yelich, PhD Department of Animal Sciences University of Florida, Gainesville

2012 Beef Improvement Federation

Houston, Texas

G. Allen Bridges, PhD University of Minnesota

North Central Research and Outreach Center Grand Rapids, MN

Bos taurus beef cattle

 Maternal and(or) terminal breeds

  Positive carcass traits: marbling,tenderness, yield

  Excellent production in temperate climates

Bos indicus Based Cattle “Positive Attributes”

  Heat tolerant

  Increased parasite & disease tolerance

  Improved production in subtropical climates

Bos indicus Based Cattle “Negative Attributes”

 Older age at puberty

  Decreased carcass quality & tenderness

  Potential handling stress issues

  Management driven

Reproductive challenges with Bos indicus cattle

  Differences in concentrations and (or) sensitivities to GnRH, LH, estrogen, and progesterone

  Increased incidence of estrous cycles with three and four follicle waves

  Difficult to detect estrus, due to shorter estrous duration, decreased estrous intensity, and increased incidence of silent heats

  Postpartum period is extended

  More susceptible to (-) effects of handling stress

Page 2: Bos taurus vs. Bos indicus

2

Synchronization Systems Producer Perspective

  Cost effective

  Ease of implementation

  Minimal cattle handlings

  Yield consistent & acceptable pregnancy rates

  Fit into producers operation

  Meet their goals and objectives

  Physical & labor resources

MANIPULATING THE ESTROUS CYCLE

Synchronization of follicular

growth & inducing ovulation for

timed-AI

GnRH ProstaglndinF2

(PG)

Regulation of CL regression

Progestogens

(MGA)

(CIDR)

Prevent expression of estrus and

induce estrous cycles

Table 1. Commonly used hormones in estrous synchronization and their trade namesa.

Hormone (Abbreviation) Commercial Productsb

Gonadotropin Hormone Releasing Hormone (GnRH)

Cystorelin!, Factrel!, Fertagyl!, OvaCyst!

Progestins

Progesterone CIDR!, Intravaginal progesterone-releasing insert

Synthetic progestin Melengestrol acetate (MGA!), Orally-active feed additive

Prostaglandin F2" (PGF) Lutalyse!, Estrumate!, ProstaMate!, estroPLAN™, In-Synch™

a Table adapted from M.L. Day and D.E. Grum, The Ohio State University

b The commercial products often do not have the same chemical composition as the hormone produced by the animal’s body. In many cases, these compounds have similar effects on the reproductive system as the native hormone. Please read and follow label instructions when using these products.

Estrous  Synchroniza0on  Terminology  

  Estrous  Response  Percentage  of  females  that  exhibited  estrus  during  synchronized  period  

  Concep;on  Rate  Percent  of  heifers  that  conceived  to  AI  of  those  that  exhibited  estrus  

  Timed-­‐AI  Pregnancy  Rate  

Percentage  of  females  that  became  pregnant  following  a  ;med-­‐AI  

  AI  or  Synchronized  Pregnancy  Rate  Percentage  of  females  that  became  pregnant  to  AI  of  total  treated  

Beef Heifer Synchronization

Estrus (Low fertility)

Synchronized Estrus & AI

1 14 16 20 31 33 38

Treatment days

MGA (14 days) PG

Brown et al., 1988

MGA + PG

Page 3: Bos taurus vs. Bos indicus

3

TRT

#

Estrous Rate (%)

Conception Rate (%)

AI Pregnancy Rate (%)

Brown et al., 1988 157 83.0 69.0 57.0

Patterson, 1990 323 83.0 74.0 61.0

Yearling Bos taurus beef heifers synchronized with MGA + PG

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Effectiveness of GnRH to induce ovulation for follicle synchronization

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Page 4: Bos taurus vs. Bos indicus

4

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Percentage Brahman (n)

Variable AN 1/4 3/8 1/2 3/4 BR

Estrous Response, %

55.6a (27)

27.6b,c (29)

38.9a.c (18)

55.6a,d (45)

40.0a,

b (20) 66.7d (24)

Conception Rate, %

53.3 (15)

62.5 (8)

71.5 (7)

56.0 (25)

50.0 (8)

75.0 (16)

Timed-AI Pregnancy Rate, %

58.3 (12)

37.9 (29)

33.3 (18)

46.7 (45)

35.0 (20)

58.3 (24)

Synchronized Pregnancy Rate, %

55.6 (27)

37.9 (29)

33.3 (18)

46.7 (45)

35.0 (20)

58.3 (24)

Select Synch + CIDR and TAI in 2 yr old Angus, Brahman, and respective crosses

a,b,c,d (P < 0.05); J.V. Yelich, unpublished data

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Page 5: Bos taurus vs. Bos indicus

5

Working  Hypothesis  

  Reducing  progesterone  concentra5ons  during  development  of  the  follicular  wave  would:  

             Progesterone  causes  an            LH  (Roberson  et  al.,  1989;  Dias  et  al.,  2009)  

  Increase  dominant  follicle  growth  and  diameter  (Carvalho  et  al.,  2008)       Increase  pre-­‐ovulatory  estradiol  produc5on  (Sirois  and  Fortune,  1990)  

  Enhance  oocyte  viability  (Revah  and  Butler,  1996)  

  Enhance  subsequent  luteal  func5on  (Butler  et  al.,  1996)  

 Increase  estrous  response  and  concep5on  rates  to  AI  and  5med-­‐AI  

Courtesy  Brandy  Sparks,  Purdue    

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Bos taurus beef heifer Synchronization

  MGA + PG and TAI

  5 Day Co-Synch + CIDR

  7 Day Select Synch + CIDR and TAI

  Response dependent on pubertal status

Bos indicus beef heifer synchronization

  Response dependent on pubertal status   MGA + PG (Split) and TAI   7 Day Select Synch + CIDR and TAI (Variable Results)

  5 Day Co-Synch + CIDR (NO!!!! NO!!!!!)

  Modified 7 Day Select Synch + CIDR and TAI

  Potential system but increased cattle handling

Page 6: Bos taurus vs. Bos indicus

6

Beef Cow Synchronization

  Suckling calf

  Decreased percentage of estrous cycling cows at breeding

  Synchronization response

•   Dependent on nutritional status pre-calving

Anestrus in US beef cattle at start of synchronization

Range 17-67% Range

6-81%

851 cows 6 locations 56 dpp

Range 8-69%

2212 cows 12 locations 69 dpp

724 heifers 5 locations 14.7 months

Lucy et al., 2001; Larson et al., 2006

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enta

ge c

yclin

g

1 3

5 7

Effectiveness of the CIDR to induce estrus in lactating anestrous (non-cycling) cows

0

10

20

30

40

50

60

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ent

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ting

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rus

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Fig 3. Synchronization responses with 7 day CIDR in Bos taurus and Bos indicus type cows

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33

0

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40

60

80

100

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Select Synch + CIDR + TAI Bos taurus1

n=498 n=332 n=539

(Larsen et al., 20061; Saldarriaga et al., 20043; Yelich, 20003, Esterman, 20112)

n=891

Select Synch + CIDR + TAI Bos indicus2

Co-Synch + CIDR

Bos taurus1

Co-Synch + CIDR

Bos indicus3

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Page 7: Bos taurus vs. Bos indicus

7

Select Synch + CIDR and TAI in suckled Bos indicus type cows

Item Year 1 Year 2 Year 3 Combined

Estrous response,% 47.6 (63) 45.2 (62) 52.9 (157) 48.5 (282)

Conception rate, % 68.8 (30) 60.7 (28) 77.1 (83) 68.8 (141)

Timed AI pregnancy rate, % 30.3 (33) 58.8 (34) 46.0 (74) 44.8 (141)

Synchronized pregnancy rate, % 50.8 (63) 59.7 (62) 62.4 (157) 57.6 (282)

Esterman et al., 2008: (Mean: BCS 5.0, DPP 75 days)

Percentage Brahman (n)

Variable AN 1/4 3/8 1/2 3/4 BR

Estrous Response, %

62.9a (70)

44.3b (70)

68.6a (35)

45.4b (97)

37.5b (32)

45.2b (31)

Conception Rate, %

68.2 (44)

54.8 (31)

50.0 (24)

72.7 (44)

50.0 (12)

57.1 (14)

Timed-AI Pregnancy Rate, %

38.5 (26)

48.7 (39)

36.4 (11)

45.3 (53)

35.0 (20)

23.5 (17)

AI Pregnancy Rate, %

57.1 (70)

51.4 (70)

45.7 (35)

57.7 (97)

40.6 (32)

38.7 (31)

a,b (P < 0.05); J.V. Yelich, unpublished data

Select Synch + CIDR and TAI in Suckled Angus, Brahman, and respective crosses

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AI pregnancy rates in Bos indicus type cows

Trt  (P  >  0.05),  Group  (P  <  0.05),  Trt  ×  Group  (P  >  0.05);  Esterman  2011  

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Page 8: Bos taurus vs. Bos indicus

8

0 5 66 hr Treatment days

Modified 5-Day Co-Synch + CIDR “Bee Synch”

Gary Williams, TAMU

CIDR

CIDR Removal & PG (2x)

CIDR Insertion & GnRH + PG

GnRH & AI

•   Suckled Bos indicus type cows: > 45 DPP > 5.0 BCS

•   AI Pregnancy Rates: 52-58%

Bos taurus Beef Cow Synchronization

  5 Day Co-Synch + CIDR

  7 Day Select Synch + CIDR and TAI

  Response dependent:   BCS, DPP, and cycling status

Bos indicus type Beef Cow Synchronization

  7 Day Select Synch + CIDR and TAI

  Variable response

  Dependent on herd management

  5 & 7 Day Co-Synch + CIDR: NO!!!! No!!!!

  Potential Systems

  Modified 7 Day Select-Synch + CIDR and TAI

  Bee Synch

  Disadvantage: increased cattle handling

Summary

  Synchronization systems in Bos taurus do not yield consistently similar results in Bos indicus type cattle

  Reasons unclear: endocrine responses/follicle dynamics

  Recently designed systems for Bos indicus show promise

  Disadvantage: additional cattle handling

Summary

  AI Synchronization success dependent on:   Cycling status in heifers/cows   BCS and DPP in cows   Maintaining system & procedure compliance

 Cost vs. Benefit

F L I G H T Z o n e

Courtesy: T. Thrift

Page 9: Bos taurus vs. Bos indicus

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